Fuel Injection/Fuel pump combination relay options

[ntownsen]

"I've searched the world over and thought I found true love ... and pfth is was gone" (you get that if you ever watched HeeHaw).

I've searched around quite a bit and I can't find a fuel injection/fuel pump combo relay. Every time I think I've found a solution, it is no longer available or its a broken link. I finally found one on ebay but they are asking $145 and that seems a little steep for a simple relay. I read some posts of people who have rewired to use more readily available parts but the descriptions were beyond my expertise. Logically since the connectors are separate, I thought I'd be able to just pick up separate relay's instead of a combo, but I haven't read anything that makes that look like a viable option. Is there an alternative, or do I just fork over the $145?

This is for a '77 280z coupe that I just can't seem to get running.

Thanks for the read.

Nathan

[Zed Head]

Here's one that's cheaper - Relay Fuel Injection 75-77: Engine Z - Electrical & Tune Up - 15097-NEE - Z Specialties Online Store - If we don't have it in stock, we can get it!

But they almost never go bad. It's usually something else. There's a procedure in the FSM, maybe the Fuel Injection Guide, for testing the relay with a meter. Much cheaper path to take.

[Captain Obvious]

"I've searched the world over and thought I found true love ... and pfth is was gone"

Heh! You're old.

Where oh where are you tonight? Why did you leave me here all alone?

And sorry... Can't help you with your quest. Thankfully I never needed to look for a replacement.

[EuroDat]

If it is the relay, and I doubt it, you can try the bosch type 0 332 514 120 New Porsche 912E96 Fuel Injection Relay 0 332 514 120 | eBay
It works on the 77 280Z. I know because Im using one.
I have a couple of spares (Jecs and Bosch) and Im with Zed Head, they don't seem to go bad very often.

Chas

[ntownsen]

Feeling older every day. Particularly when I'm upside down scrunched under the steering wheel of this ridiculously small 280z. Then unfold myself and hurt all over.

Initially I was just going to replace because ... hey relays are cheap. Planning on testing my existing relay before blowing any money. Thanks EuroDat for the part number!! Using that part number I was able to find multiple suppliers at under $90.

[EuroDat]

I found some old photos of the JECS when I had it apart. I have been using the Bosch version for two years and no issues.
I changed them because I suspected the relay, but it turned out to be a loose terminal plug in the AFM cable.

Chas

[ntownsen]

Thanks for all the info! After I found a good replacement, I went through the fuel injection supplement of the FSM tests and discovered relay is just fine but contacts may have been dirty. Now the pump is working, relay is working, pins on the ECU all test out, AFM is working fine and even have good spark ... but fuel is not making it to injectors. Previous owner started the rebuild so tank has been empty for several years ... got to get that pump primed and maybe this thing will start. Following other posts and FSM so wish me luck!

[Captain Obvious]

I pulled my pump out a while ago for refurb and I didn't have any trouble getting it to prime when I was done. I know there's a statement in some of the manuals that warns against running the car completely out of fuel because it may be hard to get pumping again, but I didn't have any issue. I pulled the starter solenoid wire and the pump primed itself and got fuel up to the rail in a few seconds. Gravity did all the work.

So you did make sure your fuel filter isn't plugged completely with crud, didn't you? Sorry, I have to ask...

If the one in the engine compartment checks out OK, there's also a small screen filter on the inlet to the pump itself. Pain to check, but that could be an issue as well.

[sblake01]

"I've searched the world over and thought I found true love ... and pfth is was gone" (you get that if you ever watched HeeHaw).

Where, where are you tonight? Why did you leave me here all alone?

(I know, it adds nothing of value to the thread but I couldn't resist.......)

[Paxhead]

Alright here is my 2 cents worth. I have been using this site for 3 years and it is very informative but I almost never comment.
I have a 77 280z 2+2 that I have turned into a race car. I have the fuel injection and on 2 different occasions I have fried the relay you are talking about. Both times while racing, the first time I was lucky and had a spare but the last time I had no spare and no way to get one in time for the race. I made a lot of inquiries and was able to rewire the car to finish racing the weekend.
The first thing I was able to do was to direct wire the fuel pump to a on/off switch. the next thing was to jumper the wires that went into the relay. Now when I say I was I mean an engineer on my team did it. I have the diagram he made on how to jumper it so I could tell you if you want to go that route. But I am still trying to figure out some of the bugs with it. The first bug is all my gauges do not work, which really sux for racing and I do not seem to be getting full power to the injectors. I can race just not as fast as before. So to sum it up it can be rewired I just haven't figured it all out yet.

[Zed Head]

I'm pretty sure that you could put your injectors on a separate power circuit just like the fuel pump. But there's really no reason not to have enough power to them. The current is dropped through the dropping resistors anyway, they only need enough to open consistently.

Gauge power could be put on a separate circuit also.

[Paxhead]

I was just guessing at the problem Zed. At full throttle in 4th gear it feels like a turbo kicking it for a second when everything runs right then back to lack of power. I still have to figure out exactly what it is.

[ntownsen]

Update.

Captain Obvious had the right idea ... looks like the tank itself is clogged. Pulled the lines off the tank with it 1/2 full and ... NOTHING. Not a dribble of gas. Drained the tank and dropped it. The inside looked like it had shag carpet the varnishing was so bad. Have run POR-15 tank cleaner through it a couple times and its looking better, but still can't even get compressed air through the return or supply. That doesn't sound normal. I'm guessing they are blocked somewhere in the tank. The cleaner doesn't seem to be clearing it. Any ideas?

I did start it up off of a gas can after I pulled the tank ... sounded great! Of course it still doesn't have an exhaust so it sounded really nasty ... my son wants to leave it that way :-)

[Captain Obvious]

Bummer. Shag carpet!! That's nasty! The good news is that you've identified the problem, right!

I think there's some internal baffling and some kind of filter inside the tank. I've (thankfully) not had to mess with that myself, but I think I remember some threads about it. And some pics.

[Paxhead]

I had the same problem and I use an extra speedo cable and plunged the metal line in the tank and it freed it up.